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export default function uniquePaths(m: number, n: number): number {    const dp: number[][] = Array(m)        .fill(0)        .map(() => Array(n).fill(0));    for (let i = 0; i < m; i++) {        dp[i][0] = 1;    }    for (let i = 0; i < n; i++) {        dp[0][i] = 1;    }    for (let i = 1; i < m; i++) {        for (let j = 1; j < n; j++) {            dp[i][j] = dp[i - 1][j] + dp[i][j - 1];        }    }    return dp[m - 1][n - 1];}